Cengage, the publisher and technology company, is introducing a subscription service that will enable students to access Cengage’s entire digital portfolio for one set price, no matter how many products they use.

The new offer, called Cengage Unlimited, will give students access to more than 20,000 Cengage products across 70 disciplines and 675 course areas for $119.99 a semester. For 12 months’ access the price is $179.99, and for two years the price is $239.99. For students taking three or four courses a semester with assigned course materials from Cengage, the subscription could offer hundreds of dollars of savings a year, versus buying or renting the products individually.

Cengage described the introduction of the Netflix-style subscription service in a press release as a “bold move”; the company has set a strategic goal of being 90 percent digital by 2019. The new strategy is a notable departure from the traditional publishing sales model, which historically has relied on the sale of individual print textbooks. Print sales have been heavily disrupted, however, by the introduction of rental programs, piracy, the sale of secondhand books and the failure by some students to purchase textbooks at all due to prohibitively high costs.

I think Cengage is vastly over-estimating its worth to its potential subscribers.

A college student taking a full-time load of 4-5 classes is unlikely to have 3-4 of those using Cengage. So that estimate of large potential savings is hardly relevant. Most students will have at most 1 or 2 courses using Cengage materials.

Much depends, of course on the price of the textbook. I teach two courses with Cengage texts that retail at $240 and $160, respectively. But students can rent those books from Amazon for $60 and $40 respectively – typically Amazon charges around 25% of the list price for a rental. (The local college bookstore charges 50%, which is one reason why no one in their right mind will rent from them.)

So, compared to renting, a student with one Cengage course loses big time under this new Cengage plan. A student with 2 Cengage courses breaks even, but only if both courses use books priced like the more expensive of my two books.